I tried the circuit brush and it's not the kind of circuit pattern I'm looking for. Also, the dodecapen causes weird lines at each corner point that I don't want on a circuit brush. The simplest brush I'm looking for is a circuit that has an hollow circle where you start the brush, and a filled circle where you end it, and I need it to be restricted to straight and diagonal lines so you can draw several bends in one stroke.

I'm having three problems with figuring it out on my own.

1: I can't figure out how to change the shape from circle to line and back again (I would like to be able to change it to other shapes in the middle as well as both ends for other circuit patterns)

2: I can't figure out how to restrict it to straight and diagonal lines. I tried using the idea from the isometric lines pattern, but it's too complex for me to figure out. I want to be able to change from straight to diagonal in the same stroke, and for the diagonal lines to be 45 degrees apart (1 to 1 pixel ratio).

3: I can't figure out how to make a regular change in the pattern, something that repeats every so often, rather than being completely randomized.

Changing the shape from a line to circle can be done with x or y scale - try it with pressure on a large size brush to see how it works. To create regular patterns try using length or time. (2) might be too tough for me.